Bernie Madoff, 70, pleaded guilty last week to 11 charges, including securities fraud and perjury, after admitting that he ran a $64 billion Ponzi scheme.

So far, about $1 billion in assets have been identified for investors, just a small portion of the billions Madoff told his 4,800 investors that he had on hand in November. Authorities say they believe the figure included what would have existed if much smaller original investments had grown for decades.

On Monday, attorneys for the trustee overseeing the liquidation of Madoff’s company’s assets filed U.S. Bankruptcy Court papers saying the trustee plans to hire a lawyer in Gibraltar to recover assets there.

“Issues have arisen overseas, and in Gibraltar in particular, that require the trustee’s participation and representation by counsel,” the filing said. “The trustee has become aware of assets that he believes to be customer property located within that country.”

At his plea, Madoff said he began what he thought would be a shortlived Ponzi scheme in the early 1990s in response to a recession. He said he never recovered and continued making payouts to early investors with money from new investors.

Prosecutors say the fraud began in the 1980s, which would make it harder for Ruth Madoff to argue that she bought the Manhattan penthouse before the fraud began.

In September, Ruth Madoff filed for a homestead exemption to protect her Palm Beach, Fla., home as her primary residence. It was granted in January, according to Palm Beach County property records.

Florida has some of the most protective laws in the country for debtors seeking to dodge creditors. “Florida is what we call a debtor haven,” said Miami bankruptcy attorney Timothy Kingcade.

But the money to buy the home cannot have resulted from fraud, Kingcade said, noting: “You can’t go rob a bank and buy a home and be protected.”